A common technique of industrial scale manufacturing of consumable filler metals is by continuously casting the weld filler alloy in the form, for example, of a rectangular bar. The continuous casting technique used for these products is by casting the bar on a casting wheel, often called a PROPERZI (trademark) wheel. The bar is subsequently in-line rolled to a round bar of about 8 to 10 mm diameter. Another common technique is the CONFORM (trademark) process, which is a continuous extrusion technique in which also a big rotating wheel is employed placed in line with a continuous casting facility to provide the feedstock for extrusion. The technique can be used as an alternative to the rolling process described above. For most welding wired the casting-rolling process is preferred over the casting-extrusion process because of the better metal quality with regard to the absence of processing contaminants such as grease.
The bars may be either directly coiled, or coiled after a rolling step, and then subsequently drawn to produce the weld filler wire of typical diameter.
Another method of industrial scale manufacturing of consumable filler metals is to cast an ingot of the weld filler alloy of predetermined chemical composition, extruding the ingot typically at elevated temperature, and afterwards the extruded rod may then be drawn into a wire. When used for welding aluminium alloys, the finished drawn wire has a diameter typically in the range of 0.5-6.0 mm.
However, these known techniques have been proven unsuitable for the production of certain weld filler metals, in particular those which become very brittle during a deformation operation possibly due to strain hardening and/or because of crack formation at elevated temperature during deformation operations due to the presence of low melting phases.